Thesis advisor: Richard Cobb-Stevens / Thesis advisor: Jean-Luc Solere / This dissertation attempts to locate the origins of Descartes' concept of mind in his early, unfinished treatise on scientific method, the <italic>Regulae ad directionem ingenii</italic>. It claims that one can see, in this early work, Descartes' commitment to substance dualism for methodological reasons. In order to begin an analysis of the <italic>Regulae</italic>, one must first attempt to resolve textual disputes concerning its integrity and one must understand the text as a historical work, dialectically situated in the tradition of late sixteenth and early seventeenth century thought. The dissertation provides this historical backdrop and textual sensitivity throughout, but it focuses on three main themes. First, the concept of <italic>mathesis universalis</italic> is taken to be the organizing principle of the work. This methodological principle defines a workable technique for solving mathematical problems, a means for applying mathematics to natural philosophical explanations, and a claim concerning the nature of mathematical truth. In each case, the <italic>mathesis universalis</italic> is designed to fit the innate capacities of the mind and the objects studied by <italic>mathesis</italic> are set apart from the mind as purely mechanical and geometrically representable objects. Second, Descartes' account of perceptual cognition, the principles of which are found in the <italic>Regulae</italic>, is examined. In this account, Descartes describes perception as a mechanical process up to the moment of conscious awareness. This point of awareness and the corresponding actions of the mind are, he claims, independent from mechanical principles; they are incorporeal and cannot be explained reductively. Finally, when Descartes outlines the explanatory bases of his natural science, he identifies certain "simple natures." These are the undetermined categories according to which actual things can be known. Descartes makes an explicit distinction between material simples and intellectual simples. It is argued that this distinction suggests a difference in kind between the sciences of the material world and the science or pure knowledge of the intellectual world. Though the <italic>Regulae</italic> is focused on physical or material explanations, there is a clear commitment to distinguishing this type of explanation from the explanation of mental content and mental acts. Hence, the <italic>Regulae</italic> demonstrates Descartes' early, methodological commitment to substance dualism. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Philosophy.

La thèse vise à expliquer dans son contexte historique les Règles pour la direction de l'esprit par rapport au concept de l'esprit cartésien. J'argue que les Règles montrent une tendance vers un concept dualiste de l'esprit. Les raisons pour cette position, je pense, sont la plupart méthodologiques. Dans les Règles, Descartes a développé les fondements philosophiques de la méthode cartésienne qui a pour objet la résolution de tous les plus célèbres problèmes de l'époque dans la science de la nature et la mathématique. Cette méthode s'est fondée sur l'idée que tous les phénomènes naturels puissent être expliqués par les modèles géométriques. Alors, pour Descartes la méthode de la science de la nature est réductive, basé sur les modèles mathématiques. En conséquence, Descartes a évidement cru que les modèles qui expliquent la nature physique ne sont pas les mêmes qui puissent expliquer la nature de l'esprit. En plus, chez les Règles, l'esprit paraît comme le véhicule de la compréhension du monde physique, et par la physiologie du cerveau et par déterminer les paramètres scientifiques de l'explication et la représentation du monde physique. Donc l'esprit est bien séparée du monde physique dans les deux sens : il ne se réduit pas aux principes physique et il organise et soutiens les principes physiques. Nous validerons cette thèse en insistant sur quatre points spécifiques: (1) l'importance historique du texte des Règles pour la pensée cartésienne, (2) la nature et l'histoire de la mathesis universalis, (3) la physiologie de la cognition, et (4) les natures simples. / The dissertation aims to contextualize and understand the Regulae ad directionem ingenii as embodying theses central to the development of Descartes' mature metaphysical concept of mind. I argue that the Regulae demonstrates a tendancy toward a dualistic concept of mind. The reasons for this, I believe, are largely methodoligical. In the Regulae, Descartes develops the philosophical foundations for a scientific method that, he thought, would allow him to solve some of the most puzzling phenomena in nature and mathematics. This method is basically predicated on the idea that all natural phenomena, i.e., physical entities, can be understood by reducing those entities to geometrical models. These geometrical models could understood and explained either mechanically or algebraically. In either case, for Descartes the scientific method is essentially reductive. As a consequence,, he clearly believes that the models that explain the physical world are not the same as those that explain the nature of the mind. Furthermore, in the Regulae, the mind appears to be a vehicle for understanding the physical world, through the physiology of the brain and by determining the scientific parameters for any representation or explanation of the physical world. Thus, the mind is truly separated from the physical world in two senses: it cannot be reduced to physical principles and it organizes and found those physical principles. We will see how this is the case by focusing on four issues: (1) the historical significance of the text in the development of Descartes' thought (2) the mathesis universalis (3) the physiology of cognition and (4) the simple natures.

De la Méthode, le VIème et dernier livre de la Recherche de la Vérité, a été consacré par Malebranche à l’exposition de sa méthode. Ce traité est toutefois demeuré en dehors des cercles d’intérêt des études malebranchistes. Le premier objectif de notre travail consiste donc à tenter de suppléer à ce manque en proposant une étude de la méthode qui mette en lumière ses aspects fondamentaux, dont, en premier lieu, le rapport qu’elle entretient avec la doctrine cartésienne des Regulae ad directionem ingenii. L’hypothèse a été soulevée que Clerselier ait pu transmettre à Malebranche le manuscrit cartésien, encore non publié à l’époque de la rédaction de la Recherche. Pour approfondir cette question, nous avons reconstruit et analysé toutes les correspondances avec les Regulae présentes dans l’œuvre. Ce dossier montre que l’hypothèse mentionnée ci-dessus est fondée : Malebranche s’inspire profondément du texte cartésien dans l’élaboration de sa méthode. Un autre aspect nous ayant semblé digne d’intérêt est le rapport entre la méthode et le problème de l’erreur, auquel Malebranche consacre les cinq premiers livres de la Recherche. L’incidence de la doctrine cartésienne de la IVème Méditation n’émerge pas sans révéler l’originalité de certaines thèses et traités du parcours de l’oratorien. Apparaît également le thème de la science universelle, ou la question de l’ordre, des questions essentielles exigeant une comparaison avec Descartes. Une comparaison qui reste toujours en toile de fond : il ne pourrait pas en être autrement puisque Descartes n’est pas seulement à l’origine de la vocation philosophique de Malebranche, mais aussi de la constitution de sa méthode. / Malebranche dedicates the sixth and final book of the Recherche de la Vérité, entitled De la Méthode, to presenting his method. This treatise has been left outside of the sphere of interest for studies on Malebranche. The primary goal of my work is to fill this gap and provide a study on the method by highlighting some of its key aspects. The first of these concerns its relationship with the Cartesian doctrine of Regulae ad directionem ingenii. Clerselier is assumed to have notified Malebranche of the Cartesian manuscript, which had not yet been published at the time of writing the Recherche. To examine this very question, I have reconstructed and analysed all correlations with the Regulae found within the work. This dossier demonstrates the validity of the above assumption: that his knowledge of this Cartesian text greatly inspired Malebranche as he developed his method. Another noteworthy aspect I have explored is the method’s relationship with the issue of error, which is addressed by Malebranche in the first five books of the Recherche. The influence of the Cartesian doctrine of the fourth Meditation does not emerge without revealing the originality of certain arguments and certain parts of Malebranche's development. There is also the topic of universal science and that of order – essential issues that naturally allude to the comparison with Descartes. This comparison always and inevitably remains in the background: Descartes is found not only at the origin of Malebranche’s philosophical calling, but also in the construction of his method.

Cette thèse étudie la question de savoir pourquoi et comment Descartes peut définir la science comme une combinaison de jugements vrais dans les "Regulae a directionem ingenii" et dans les "Meditationes de Prima Philosophia", sans concevoir l'acte de juger et la structure des jugements dans les mêmes termes dans ces textes. De "Reguale" aux "Mediationes", Descartes passe en effet d'une fondation du jugement sur l'entendement à une fondation du jugement sur la volonté, et d'un rejet d'une composition prédicative qui reproduirait la composition réelle des choses à une prise de distance par rapport à cette indifférence ontologique. On explique le passage de la première théorie cartésienne du jugement à la seconde par l'évolution de la théorie et de la pratique cartésienne de la science : après avoir fait du jugement l'énoncé de rapports entre les paramètres d'une "quaestio", mathématique ou physique, Descartes s'intéresse spécifiquement à la physique, et il pense le jugement comme l'expression des attributs et des modes de la substance corporelle, conformément à la distinction réelle de l'âme et du corps démontrée dens les "Meditationes". Dans cette perspective, l'accent finalement mis sur la volonté a une sens épistémique. Il exprime la nécessaire subordination de toute affirmation à une conception claire et distincte de l'objet examiné. On introduit au rôle de substitut de la logique des théories cartésiennes du jugement par un rappel de la prise de position de Descartes par rapport à la logique scolastique et aux critiques adressées par ses contemporains à celle-ci. Dans une première partie, on analyse la place réservée à ces théories dans la constitution de logiques cartésiennes / In the "Regulae" and in the "Mediationes", Descartes defines science as a combining of true judgments. However, in these works, he does not conceive the act of judging and the structure of judgments in the same way. In the "Regulae", a judgment is produced by the intellect ; in the "Meditationes", it depends on the will. In the "Regulae", Descartes rejects the idea that the construction of a judgment about how things are related is simply a mental mirroring of how those things are related in the world. In the "Mediationes", he bases predication on three notions which play the part of categories : thought, extension, union. We account for this development by referring to some changes in Descartes'approach to science, end to his progressive focus on physics. Consequently, we show that, although, in the first place, Descartes reduces judgment to the affirmation of the relationship between the parameters of a given "quaestio", taken either from the field of mathematics or from the field of physics, later, in the 1630's, he focuses on physics and conceives of judgment as the expression of the properties of the extended substance. Our study of the function and nature of Descartes'concept of judgment is introduced by considering the meaning of the term "judgment" among Descartes' contemporaries (Late Scholastics, Montaigne, Bacon, Ramus). It ends with an examination of the reception of Descartes' theories of judgment in Clauberg's "Logica Vetus et Nova", in the "Port-Royal Logic" and in Malebranche's "Search after Truth"

Though generally recognized as a formative force in his philosophy, Thomas Reid’s Newtonianism and his philosophy of science has not received due attention among scholars. My aim is to inaugurate a detailed survey. In ch. 1 it is shown that Reid demarcates physics as against metaphysics and theology, making his brand of Newtonianism different from first generation moral and religious Newtonianism. In ch. 2 it is argued that "Newtonian" is not an apt label on Reid’s call for a Science of the human mind. Neither his practice within the field, nor his methodological views, make lawlike connections the central kind of truth to be discovered. Ch. 3 is devoted to Reid’s account of the 1st and 2nd of Newton’s Regulae Philosophandi, and an ensuing notion of explanation which approaches the deductive-nomological model. It is shown that Reid’s account is very much his own, though presented as an explication of Newton’s intentions. Reid’s dismissive view towards simplicity as a guide in scientific reasoning leans on Bacon’s theory of idols and Reid’s theory of first principles of common sense. Ch 4 concerns hypotheses in connection with Newton’s phrase Hypotheses non fingo. It is argued that Reid does not mind speculation about unobservable or theoretical entities, and that his objections to particular ether theories are scientific rather than principled. Nonetheless, since Reid does not explain the difference between powerful conjecture and established truth, his notion of scientific reasoning remains elusive. Ch 5 concerns Reid’s views on the concept and ontology of forces of attraction. It is argued that Reid takes forces to be physical entities open for empirical enquiry, and that forces are neither active, nor efficient. Finally, Reid’s view of metaphysics is considered, and further differences with early Newtonians emphasised.